Abstract

Laser driven protonacceleration experiments from micron and submicron thick targets using high intensity (2 × 1021 W/cm2), high contrast (10−15) laser pulses show an enhancement of maximum energy when hydrogen containing targets were used instead of non-hydrogen containing. In our experiments, using thin (<1μm) plastic foil targets resulted in maximum protonenergies that were consistently 20%–100% higher than when equivalent thickness inorganic targets, including Si3N4 and Al, were used. Protonenergies up to 20 MeV were measured with a flux of 107 protons/MeV/sr.

This work was supported by the NSF through the Physics Frontier Center FOCUS (Grant No. PHY-0114336) and GRFP (Grant No. DGE-0718128), as well as from the Office of Naval Research and the Defense Threat Reduction Agency (DTRA).